Dihydroxyphenyl compounds and glucoside compounds thereof

ABSTRACT

The present invention is a compound represented by the following formula (1) or (2):  
                 
 
     where one of R 1  and R 2  is hydrogen and the other one is hydrogen or glucose residue. The compound is effective for reforming obese constitution, suppressing or preventing obesity. It is also effective for skin whitening.

FIELD OF THE INVENTION

[0001] The present invention relates to dihydroxyphenyl compounds andglucoside compounds thereof which are useful to reform obeseconstitution by promoting shrinkage of general or topical fat tissues,or to suppress or prevent obesity by preventing the fat tissue fromswelling.

[0002] The present invention relates also to dihydroxyphenyl compoundsand glucoside compounds thereof which are effective for skin whitening.

DESCRIPTION OF THE PRIOR ART

[0003] Intercorporal fat is neutral fat present in white adipose tissuesproduced from surplus energy intake remaining after energy consumption.Obesity due to heavily accumulated intercorporal fat is not onlyaesthetically unfavorable, but also causes various diseases, such asarteriosclerosis. Recently, more and more people suffer from obesity dueto excessive eating, lack of exercise, and/or stress. On the other hand,a slim and tight body is yearned for particularly by women from theviewpoint of appearance. Accumulation of subcutaneous fat is unfavorablefor health, so that reduction of the fat or prevention of theaccumulation thereof is important.

[0004] Meanwhile, capsaicin contained in Capsicum is known to be capableof preventing obesity by bonding to blood albumin and secreting hormonewhich promotes adrenal metabolism and activates energy metabolism inlever or fat cells (Kazuo Iwai and Nobuji Nakatani, Function of SpiceIngredients in Foods, 97(1989), Koseikan, Tokyo). However, capsaicin isstrongly irritant and thus has limited applications or is used in alimited amount.

[0005] The present inventors speculated that it is difficult to diminishaccumulated fat cells, but it is easier to make the cells smaller bydecomposing lipid droplets in the cells.

[0006] The lipid droplet can be decomposed with an enzyme, phospholipaseC, in a similar manner as protein. However, it is surrounded by ahydrophobic phospholipid membrane, so that the enzyme present inendoplasmic reticulum which is a mass of water cannot obtain access tothe lipid droplet.

[0007] Meanwhile, sympathetic nerves are activated by taking exercise tosecrete fat decomposing hormone. This hormone is believed to remove thephospholipid membrane to allow the enzyme to obtain access the lipiddroplets to thereby promote lypolysis. Therefore, the present inventorsendeavored to find a substance which promotes accessibility of theenzyme to the lipid droplets in a similar manner as the hormone.

[0008] As a result, the present inventors found that raspberry ketone,zingerone and derivatives thereof promote decomposition of fataccumulated in fat tissues and, thus, are effective to suppress obesityor to reform obese constitution(Japanese Patent Application Laid-openNo. 2000-169325). However, both raspberry ketone and zingerone havetheir peculiar odor and taste and consequently their amounts of dosageand versatility are limited.

[0009] Thus, a lypolysis promoter, skin cosmetic composition, and foodor drink composition which have satisfactory versatility and an effectof preventing formation of or reducing subcutaneous fat are desired.

[0010] Meanwhile, there is strong desire for white skin and,accordingly, it is desired to prevent or lighten erythema, melanization,stains, or freckles due to skin damages caused by UV light. To lightenthe damage caused by UV light leads to suppressing photo-aging whichcauses wrinkles. Thus, a skin cosmetic composition having effects ofpreventing erythema and of whitening is desired.

[0011] In view of the above discussion, it is an object of the presentinvention to provide a substance which is effective for reforming obeseconstitution by promoting shrinkage of general or topical fat tissues,or suppressing or preventing obesity by preventing swelling of the fattissues, and which substance has no odor or taste and has excellentversatility.

[0012] Another object of the present invention is to provide a skincosmetic composition which has an excellent whitening effect.

SUMMARY OF THE INVENTION

[0013] The present inventors have found that a compound represented bythe following formula (1) or (2):

[0014] where one of R¹ and R² is hydrogen and the other one is hydrogenor glucose residue, is effective for reforming obese constitution orsuppressing or preventing obesity by promoting lypolysis and haswhitening effect to thereby attain the aforesaid objects.

[0015] Thus, the present invention is a compound represented by theformula (1) or (2).

[0016] Further, the present invention is a lipolysis promoter or amelanogenesis inhibitor represented by the formula (1) or (2). Stillfurther, the present invention is a skin cosmetic composition or a foodor drink composition comprising the compound represented by the formula(1) or (2).

[0017] Also provided is a method for reducing a body weight by orallydosing or applying to skin the lyolysis promoter represented by theformula (1) or (2).

BRIEF DESCRIPTION OF THE DRAWINGS

[0018]FIG. 1 shows a GC-MS total ion chromatogram(top) and a massspectrum(bottom) of 4-(3′, 4′-dihydroxyphenyl)-butane- 2-one of thepresent invention.

[0019]FIG. 2 shows a ¹³C-NMR spectrum of 4-(3′,4′-dihydroxyphenyl)-butane- 2-one of the present invention.

[0020]FIG. 3 shows a GC-MS total ion chromatogram and a mass spectrum of4-(3′, 4′-dihydroxyphenyl)-butane- 2-ol of the present invention.

[0021]FIG. 4 shows a ¹³C-NMR spectrum of 4-(3′,4′-dihydroxyphenyl)-butane- 2-ol of the present invention.

[0022]FIG. 5 shows a ¹H-NMR spectrum of 4-(3′,4′-dihydroxyphenyl)-butane- 2-ol of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] The present invention will be explained in detail.

[0024] Japanese Patent Application No.11-42937 by the present applicantwas published on Sep. 5, 2000(JP Laid-open No. 2000-239143), whichdescribes some species of the present compound as an active ingredientfor a skin cosmetic composition having melanogenesis inhibition effect.

[0025] The compound of the aforesaid formula (1) wherein R¹ and R² areboth hydrogen, 4-(3′, 4′-dihydroxyphenyl)-butane-2-one, may be easilyprepared by the method described in the above application. Specifically,it may be easily prepared by cleavage of C—O bond of methylether ofzingerone, [4-(3′-methoxy-4′-hydroxyphenyl)-butane-2-one], which iscontained in ginger, in a known manner with, for example, borontribromide or hydriodic acid.

[0026] The compound of the formula (1) wherein R¹ or R²is glucoseresidue may be obtained by extracting it from plants, such asraspberries, with an appropriate solvent and, if necessary, condensingor evaporating the solvent to dryness in a known method(seePhytochemistry, Vol. 29, No.12, 3853-3858(1990)). Alternatively, it maybe prepared by condensing 3,4-dihydroxy benzaldehyde with acetone andreducing the condensate by a conventional method.

[0027] The compound of the aforesaid formula (2) wherein R¹ and R² areboth hydrogen, 4-(3′, 4′-dihydroxyphenyl)-butane-2-ol, may be preparedin a similar manner as described above, starting from4-(3′-methoxy-4′-hydroxyphenyl)-butane-2-ol obtained by reducingzingerone with sodium borohydride. It may also be prepared by reducingthe compound of the formula (1) by a conventional method.

[0028] The compound of the formula (1) or (2) may be used alone or incombination of two or more of them as a lypolysis promoter or awhitening agent. An amount of the present compound to be incorporated ina skin cosmetic composition or a food or drink composition intended tobe used for reducing weight may vary depending on the form of thecomposition. In the skin cosmetic composition for reducing weight, thepresent compound is incorporated preferably in an amount of from 0.001to 20 wt %, more preferably from 0.01 to 5.0 wt %, most preferably from0.05 to 3.0 wt % based on the weight of the composition. In the food ordrink composition for reducing weight, the present compound isincorporated preferably in an amount of from 0.001 to 20 wt %, morepreferably from 0.01 to 10.0 wt %, most preferably from 0.01 to 3.0 wt %based on the weight of the composition. If the amount is less than theaforesaid lower limit, an effect of the present invention may not beattained. If the amount is more than the aforesaid upper limit, theeffect may not increase correspondingly. In askin cosmetic compositionwith a major purpose A of whitening, the present compound isincorporated preferably in an amount of from 0.01 to 5 wt % based on theweight of the composition.

[0029] In the present skin cosmetic composition, any known substancescan be incorporated in addition to the aforesaid present compounds, forexample, those conventionally used in a skin cosmetic composition suchas fats and oils, pigments, surfactants, humectants, UV absorbers,anti-inflammatories, fungicides, antiseptics, and colorants;β-adrenaline action stimulants, such as butopamine and isoproterenol;α2-adrenaline action depressants such as yohimbine and ergotoxine;xanthine derivatives, such as theophylline and caffeine; bipyridinederivatives, such as milrinone and amrinone; and those which suppress orprevent obesity, such as raspberry ketone and zingerone.

[0030] In the present food or drink composition, any known substancescan be incorporated in addition to the aforesaid present compounds, forexample, those conventionally used in a food or drink composition, suchas saccharides, perfumes, emulsifiers, milk products, proteins,stabilizers, colorants, acidulants, fats and oils, cereals, eggs, gumbase; xanthine derivative such as caffeine; hydroxy citric acid; andthose which suppress or prevent obesity, such as capsaicin, raspberryketone, zingerone and synephrine.

[0031] The present lypolysis promoter can be incorporated in food, oraldrugs, or skin cosmetics in any dosage form. For example, the skincosmetics for reducing weight may be of a form of cream, milky lotion,gel, stick, sheet, cataplasm, powder, liquid or granule to be applied toskin, for bathing, or for washing. The food or drink composition may beincorporated in chewing gum, chocolate, candies, gummy jellies, soup,ice cream, noodles, or bakery products.

EXAMPLES

[0032] The present invention will be explained in details with referenceto the following Examples and Comparative Examples. Efficacy oflypolysis promotion was evaluated in the lypolysis test and in thesubcutaneous fat decomposition test described below. Commerciallyavailable raspberry ketone and zingerone were used.

Preparation Example 1 4-(3′, 4′-dihydroxyphenyl)-butane-2-one

[0033] Zingerone, [4-(3′-methoxy-4′-hydroxyphenyl)-butane-2-one], wasdissolved in dichloromethane, to which 1.0 mol/l boron tribromidesolution in dichloromethane was then added at −30° C. While stirring,the reaction mixture was gradually heated to a room temperature andallowed to react for further2 hours at the temperature. After adding icewater to the reaction mixture, an aqueous 2% sodium hydrogen carbonatesolution was added. Then, the reaction mixture was extracted with ethylacetate, and the ethyl acetate layer thus obtained was dried withanhydrous magnesium sulfate. Then, the ethyl acetate layer was vacuumcondensed to obtain brown oil which was purified by silica gelchromatography, using a mixture of hexane/ethyl acetate =7/3 as adeveloping solvent. The white crystals thus obtained had almost no tasteand no odor. Chemical structure was confirmed to be 4-(3′,4′-dihydroxyphenyl)-butane-2-one by GC-MS and NMR(see FIGS. 1 and 2).

Preparation Example 2 4-(31, 4′-dihydroxyphenyl)-butane-2-ol

[0034] The procedures in preparation Example 1 were repeated except thatuse was made of 4-(3′-methoxy-4′-hydroxyphenyl)-butane-2-ol obtained byreducing zingerone with sodium borohydride, instead of zingerone. Thewhite crystals thus obtained had almost no taste and no odor. Chemicalstructure was confirmed to be 4-(3′, 4′-dihydroxyphenyl)-butane-2-ol byGC-MS and NMR(see FIGS. 3, 4 and 5).

Method for Determination of Lypolytic Activity

[0035] Free fat cells were prepared from epididymis fat tissues ofWister male rats(body weight, 150 to 200g) using a collagenase solution,according to Rodbell's method(M. Rodbell, J.Biol.Chem., 239,375(1964)).The cells were added to a Hanks' balanced salt solution containing 0.05μg/ml of bovine serum albumin, 0.05 μg/ml of norepinephrine and100/μg/ml of the present compound to be tested, and then allowed toreact at 37° C. for 1 hour. Liberated fatty acids were extracted andquantitated with a copper reagent and a color developing reagent.Lypolytic activity was calculated according to the following equation.

Lypolytic activity (%)=[A/B] ×100,

[0036] wherein

[0037] A: amount of fatty acids in a sample solution, and

[0038] B: that in a control solution without present compound.

Subcutaneous Fat Decomposition Test

[0039] Wister rats (male, 7 to 9 weeks old) were shaved at theirbellies. Then, the belly cortex was enucleated together withsubcutaneous fat tissues and mounted on Franz-type diffusion cells witha diameter of 2 cm. The keratin held in the upper cell was uniformlycoated with 0.5 g of the present skin cosmetic composition and the lowercell for the subcutaneous tissue side was filled with a phosphate-buffersaline at pH 7.2. After keeping the cell at 37° C. for 6 hours, analiquot of the buffer solution was taken out from the lower cell andglycerol liberated in the solution was quantitated by an enzyme methodwith F-kit Glycerol, ex Beringer Manheim Co. For each sample, thequantification was repeated five times and data were averaged.

Example 1 And Comparative Example 1

[0040] The lypolytic activity was determined on the present lypolysispromoter and raspberry ketone for comparison. TABLE 1 degree oflypolysis promotion Lypolysis promoter (%) Example 1 4-(3′,4′- 194.3 +/−12.4 dihydroxyphenyl)- p < 0.001 butane-2-one Comparative Example 1Raspberry ketone 142.0 +/− 6.8  p < 0.01

[0041] The present lypolysis promoter of Example 1 showed significantlyhigher lypolytic activity, compared with raspberry ketone of ComparativeExample 1.

Examples 2, 3 And Comparative Examples 2 and 3 (Gel Type Skin CosmeticComposition for Reducing Weight)

[0042] Parts A and B were separately prepared by mixing and dissolvingthe substances in the amounts as shown in Table 2 in a conventionalmethod. Then Part B was added to Part A with stirring to obtain a geltype skin cosmetic composition for reducing weight. TABLE 2 Com- Com-parative parative Part (wt %) Example 2 Example 3 Example 2 Example 3Part A 4-(3′,4′-dihydroxy 1.0 3.0 — — phenyl)-butane-2-one Raspberryketone — — 1.0 — Glycerol 10.0 10.0 10.0 10.0 Carboxyvinyl polymer 0.30.3 0.3 0.3 Disodium edetate 0.1 0.1 0.1 0.1 Purified water balancebalance balance balance Diisopropanolamine 1.0 1.0 1.0 1.0 Squalane 10.010.0 10.0 10.0 Part B Polyoxyethylene (60) 0.8 0.8 0.8 0.8 hydrogenatedcastor oil Carrageenan 3.0 3.0 3.0 3.0 Xanthan gum 3.0 3.0 3.0 3.0Polyvinylalcohol 2.0 2.0 2.0 2.0 Ethanol 45.0 45.0 45.0 45.0 Menthol 0.10.1 0.1 0.1 Perfume small small small small quantity quantity quantityquantity

[0043] The results of the subcutaneous fat decomposition test on theaforesaid gel type skin cosmetic compositions are as shown in Table 3.TABLE 3 Liberated Glycerol (μmol/ml) Example 2 174.5 Example 3 191.6Comparative Example 2 132.4 Comparative Example 3 60.8

Example 4 And Comparative Examples 4 and 5( In Vivo Test on Obesity byHigh-Calorie Diet)

[0044] Each seven ICR mice per group(female, 5-week old at the beginningof the test, average body weight of 31 g) were bred for 3 weeks withhigh-calorie diet (Comparative Example 4) or high-calorie diet to which4-(3′, 4′-dihydroxyphenyl)-butane-2-one was added(Example 4) or astandard feed(solid standard feed MF, ex Oriental Yeast Co.) for acontrol group(Comparative Example 5). The mice were allowed to freelyintake feed and drinking water, and weighed on the final day of the testperiod. Composition of the feed and the results are as shown in Tables 4and 5, respectively. TABLE 4 Feed Composition Comparative ComparativeExample 4 Example 4 Example 5 (Control) wt % wt % Solid standard feedBeef tallow 40  40 MF, ex Oriental Corn starch 10  10 Yeast Co.Granulated sugar 9 9 Mineral*¹ 4 4 Vitamine*² 1 1 Casein 35  364-(3′,4′- 1 — dihydroxyphenyl)- butane-2-one

[0045] TABLE 5 Results Comparative Example 5 Comparative (Control)Example 4 Example 4 Average weight (g) 38.1 38.4 43.2 Weight increment(g) 7.1 7.4 12.2

Example 5 Melanogenesis Inhibition Test

[0046] B16 melanoma cells were inoculated in a 12 wells-plastic plate ata concentration of 2×10⁴/well on MEM(Minimum Essential Medium). After 24hours, the medium was changed to a Theophylline containing medium towhich 4-(3′, 4′-dihydroxyphenyl)-butane-2-one was added in theconcentrations shown in Table 6. The cells were cultured for 72 hoursand then treated with 10% TCA and ethanol/diethylether(=1/1). Aftercounting the number of the cells, the cells were dissolved in an aqueous1 mol/l sodium hydroxide solution containing dimethylsulfoxide in aconcentration of 10%. Optical density at 475 nm (OD475 ) of the solutionthus obtained was measured. The amount of the produced melanin per cellwas calculated from OD475 and expressed in percentage relative to theamount observed in the blank sample where cells were cultured on amedium which did not contain 4-(3′, 4′-dihydroxyphenyl)-butane-2-one.TABLE 6 4-(3′,4′- dihydroxyphenyl)- butane-2-one concentration Amount ofmelanin per (μg/l) cell (%) Standard deviation 0 100 11.2 1 97.4 3.4 377.2 2.2 10 62.7 2.5 30 2.2 0.3

[0047] There was no difference among the numbers of the cells in theaforesaid concentration range of the present compound.

Example 6 Anti-Oxidation Test

[0048] To 1 ml of methyl linolate, 0.005g of the present compound wasadded, which was then irradiated with UV light with a UV lightirradiation apparatus, M-DMR, ex Toshiba Co.. The amount of peroxidesformed by oxidation of methyl linolate was determined according to amethod described in Akasaka et al.,Bioscience/Biotechnology/Biochemistry, Vol. 58, 396(1994), usingdiphenyl-1-pyrenylphosphine as a fluorescent labeling agent. Comparativetest on raspberry ketone was made in the same manner as above. Theresults are as shown in Table 7. TABLE 7 UVB 10 (J/cm²) UVB 30 (J/cm²)Raspberry ketone 30.2 42.5 4-(3′,4′-dihydroxyphenyl)- 1.6 3.7butane-2-one

Examples 7 to 12

[0049] Skin lotion were prepared from the components as shown below andin Table 8. Parts Amount (wt %) (A) Ethanol 10.0 Monolauric acid 5.0polyoxyethylene (20) sorbitan Dibutylhydroxytoluene 0.01 Perfume 0.05(B) The present compound described in Table 8 (C) Glycerol 5.0 Xanthangum 0.1 Hydroxyethylcellulose 0.1 Purified water balance

[0050] TABLE 8 Sample Amount (wt %) Example 7 4-(3′,4′- 3.0dihydroxyphenyl)- butane-2-one Example 8 4-(3′,4′- 0.5 dihydroxyphenyl)-butane-2-one Example 9 4-(3′,4′- 0.01 dihydroxyphenyl)- butane-2-oneExample 10 4-(3′,4′- 3.0 dihydroxyphenyl)- butane-2-ol Example 114-(3′,4′- 0.5 dihydroxyphenyl)- butane-2-ol Example 12 4-(3′,4′- 0.01dihydroxyphenyl)- butane-2-ol

Preparation Method

[0051] Part B was homogeneously dissolved in Part C, to which Part A wasadded with stirring to be dispersed homogeneously. The product thusobtained was poured in a container.

Examples 13 to 18 Skin Cream

[0052] Skin creams were prepared from the components shown below and inTable 9. Part Amount (wt %) (A) Glycerol monostearate 2.0 Beeswax 1.0Monooleic acid polyoxyethylene (6) 1.0 sorbitan Vaseline 4.0 Liquidpetrolatum 12.0 (B) The present compound described in Table 9 (C) SodiumN-stearoyl-L-glutamate 5.0 Carrageenan 0.3 Methylparaben 0.1 Purifiedwater balance

[0053] TABLE 9 Sample Amount (wt %) Example 13 4-(3′,4′- 3.0dihydroxyphenyl)- butane-2-one Example 14 4-(3′,4′- 0.5dihydroxyphenyl)- butane-2-one Example 15 4-(3′,4′- 0.01dihydroxyphenyl)- butane-2-one Example 16 4-(3′,4′- 3.0dihydroxyphenyl)- butane-2-ol Example 17 4-(3′,4′- dihydroxyphenyl)- 0.5butane-2-ol Example 18 4-(3′,4′- 0.01 dihydroxyphenyl)- butane-2-ol

Preparation Method

[0054] Part A and a mixture of Components B and C were separately heatedto 80° C. to make homogeneous solutions. Then, Part A was added to themixture of Parts B and C and emulsified. The emulsion thus obtained wascooled to 30° C. with stirring.

Example 19 Chewing Gum

[0055] Chewing gum with the following composition was prepared. wt % Gumbase 20 Maltitol 73.5 Reduced glutinous starch syrup 4 Apple flavor 0.5Garcinia Cambogia Extract*¹ 1 4-(3′,4′-dihydroxyphenyl)-butane-2-one 1

Example 20 Sweet Tablets

[0056] Sweet tablets with the following composition was prepared. wt %Sorbitol 72.9 Sucrose ester of fatty acid 4 Raspberry flavor 0.1Garcinia Cambogia Extract 3 4-(3′,4′-dihydroxyphenyl)-butane-2-one 10

1. A compound represented by the following formula (1) or (2):

where one of R¹ and R² is hydrogen and the other one is hydrogen orglucose residue.
 2. A lipolysis promoter represented by the followingformula (1) or (2):

where one of R¹ and R² is hydrogen and the other one is hydrogen orglucose residue.
 3. The lipolysis promoter according to claim 2, whereinR¹ and R² are both hydrogen.
 4. A melanogenesis inhibitor represented bythe following formula (1) or (2):

where one of R¹ and R² is hydrogen and the other one is hydrogen orglucose residue.
 5. The melanogenesis inhibitor according to claim 4,wherein R¹ and R² are both hydrogen.
 6. A skin cosmetic compositioncomprising the compound according to claim
 1. 7. The skin cosmeticcomposition according to claim 6, wherein the compound is incorporatedin an amount of from 0.00 1 to 20 wt % based on the weight of thecomposition.
 8. The skin cosmetic composition comprising according toclaim 7, wherein the compound is incorporated in an amount of from 0.01to 5 wt % based on the weight of the composition.
 9. A food or drinkcomposition comprising the compound according to claim
 1. 10. The foodor drink composition according to claim 9, wherein the compound isincorporated in an amount of from 0.001 to 20 wt % based on the weightof the composition.
 11. A method for reducing a body weight by orallydosing or applying to skin the lipolysis promoter according to claim 2or 3.